title: Alveolar bone thickness and lower incisor position in skeletal Class I and Class II malocclusions assessed with cone-beam computed tomography.
abstract: OBJECTIVE
  To evaluate lower incisor position and bony support between patients with Class II average- and high-angle malocclusions and compare with the patients presenting Class I malocclusions.
  
  
  METHODS
  CBCT records of 79 patients were divided into 2 groups according to sagittal jaw relationships: Class I and II. Each group was further divided into average- and high-angle subgroups. Six angular and 6 linear measurements were performed. Independent samples t-test, Kruskal-Wallis, and Dunn post-hoc tests were performed for statistical comparisons.
  
  
  RESULTS
  Labial alveolar bone thickness was significantly higher in Class I group compared to Class II group (p = 0.003). Lingual alveolar bone angle (p = 0.004), lower incisor protrusion (p = 0.007) and proclination (p = 0.046) were greatest in Class II average-angle patients. Spongious bone was thinner (p = 0.016) and root apex was closer to the labial cortex in high-angle subgroups when compared to the Class II average-angle subgroup (p = 0.004).
  
  
  CONCLUSIONS
  Mandibular anterior bony support and lower incisor position were different between average- and high-angle Class II patients. Clinicians should be aware that the range of lower incisor movement in high-angle Class II patients is limited compared to average- angle Class II patients.
authors.affiliation: Department of Orthodontics, Faculty of Dentistry, Izmir Katip Celebi University, Izmir, Turkey.
authors.forename: Asli
authors.initials: A
authors.lastname: Baysal
authors.forename: Faruk Izzet
authors.initials: FI
authors.lastname: Ucar
authors.forename: Suleyman Kutalmis
authors.initials: SK
authors.lastname: Buyuk
authors.forename: Torun
authors.initials: T
authors.lastname: Ozer
authors.forename: Tancan
authors.initials: T
authors.lastname: Uysal
keywords: 3 Dimensional diagnosis and treatment planning; Class II